(a) Field of the Invention
The present invention relates to a method for detecting a signal, a device for detecting a signal, and a receiving device.
(b) Description of the Related Art
With the development of wireless communication systems, the demand for speed has increased. In order to meet the demand, a need exists for a use of a wide frequency bandwidth. However, frequency resources are limited. Therefore, as a method for transmitting more data while using a limited frequency bandwidth, a multi-input multi-output (MIMO) antenna technology has been used.
The multi-input multi-output antenna technology is largely sorted into a spatial diversity scheme that obtains a diversity gain corresponding to a product of the number of transmitting antennas and the number of receiving antennas to improve reliability of transmission, and a spatial multiplexing (SM) scheme that transmits other data streams via different paths.
In the case of the spatial multiplexing scheme, since mutual interference can occur between different data streams, a receiver should detect a signal in consideration of the interference and decode it. The signal detecting scheme may include a scheme for obtaining maximum likelihood of each data bit, a linear detecting scheme, a non-linear detecting scheme, etc. However, the maximum likelihood scheme cannot be easily implemented since it is too complicated due to the number of antennas, etc. The linear detecting scheme may include a zero forcing (ZF) scheme and a minimum mean square error (MMSE) scheme. These schemes have low complexity but the performance thereof is deteriorated due to noise amplification. The non-linear detecting scheme may include an ordered successive interference cancellation scheme (OSIC) called vertical Bell lab layered space-time (VBLAST) architecture. This can be relatively easily implemented but does not have satisfactory performance.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.